Waterproof under sink?

This isn't really a plumbing question, I guess, but didn't know where to post.

Anyway, I have just repaired a leaking drain in the kitchen sink, and the composite wood floor in the cabinet under the sink soaked up a fair amount of water. I was wondering is there is something I can use to treat it so the water would bead instead of soak in. (I had shelf paper in there, but it ran to the side and under it.) Any advice> Thanks.

In a lot of rental properties that I worked regularly on, I would caulk all the sides and backs at the bottom, and coat the bottom of the cabinet with a clear spar varnish. I preferred to do this, than come back sooner or later to find the particle board cabinet bottom swelled up like a baloon!@

If the leak is fixed I wonder why you are worried. But, I used Rain-X on the bottom, but, I only used a very small amount. Really, just a dobber on a paper towel. I wouldn't use any of the Nanotechnology products because of the possible contents/ I wouldn't use them indoors.

I just used a regular Rain X, I was careful to use only a small amount, I wasn't sure what it would do, like mar the finish of the wood, or be harmful, but, it seems ok to me. It beads up the water if it leaks. The varnish would probably be better, I bet. But, I just had it sitting in the garage and thought I would try it. I also keep a small bucket under the sink, under the plumbing, and this way too, it is convienent for needing a bucket in the kitchen for cleaning; and just incase it leaks, the bucket is there to catch it. Instead of a contact paper or shelf paper, you could lay down a piece of vinyl flooring.